There is frequently a need to determine whether a container, for instance one containing medicine, tablets or the like, has been previously opened. Many closures assuring intactness are already known for this purpose. In principle, an element insuring intactness is always provided, such that in the original state of the closure cap the element is firmly connected with the rest of the cap, then being separated from it when the cap is unscrewed from the associated bottle for the first time at predetermined separation points. In most cases, a reduction in wall thickness or a perforation through the cap wall is provided, so that axially parallel or radial tear strips remain.
The closure caps are placed on the associated containers with the aid of closure machines, which have closing heads that surround the closure cap and press or screw the cap onto the container when rotated appropriately, thus closing the containers.
The predetermined separation points or tear strips must accordingly be strong enough to withstand the forces exerted during the closure process (the process of screwing the caps onto the containers). Otherwise, a separation of the closure cap and the element assuring intactness would take place as the container is being closed, rather than when the container is opened for the first time.
Closure machines have become known in recent years which operate at a highly elevated speed of rotation. As a result, the forces (torque) exerted upon the predetermined separation points or tear strips are greatly increased, and the previously known closure caps having elements assuring intactness cannot be processed on such closure machines.